i would also suggest the Hi Point because of it's price. i would rather see a less than $200 Hi Point sink to the bottom of a lake than a very expensive pistol. spray it with a good gun oil and keep it in a zip lock bag for protection.

If you're just taking the pistol out on day trips and not living on the boat or doing long cruises, most any quality pistol will do. Sig, Berretta, Glock or a quality 1911 would all work even if they got dunked. The key is to clean them when you get home, especially if you boat on saltwater. Also decent Smith & Wesson revolvers or Rugers.

What do you want it for, gators, snakes, sharks, or bad guys?

My grandfather would take out an old Mauser rifle in the ocean, or if he was running in rivers he took the rifle or a single shot shotgun.

Some of the guys down here in S.E. Georgia will keep a .44 revolver or a cheap rifle in the boat in case they see hogs on the river banks.

Most modern ammo will survive getting wet. Some can be soaked for awhile. I forgot to remove a speed strip full of Gold Dot ammo from my pocket before washing my pants. I removed these rounds from my carry stash and used tehm the next time I was practicing. They all worked and hit to point of aim.